1. Technical Field
The present disclosure generally relates to display technology, and particularly to a liquid crystal display (LCD) device and a method for driving the LCD device.
2. Description of Related Art
LCD display has advantages of low power consumption and low radiation, and has been widely used in various portable information products such as notebooks, personal digital assistants (PDAs), video cameras and the like. Conventionally, an LCD device includes a display panel. The display panel usually includes a plurality of gate lines and a plurality data lines insulated from and intersecting the plurality of gate lines. The plurality of gate lines and the plurality data lines define a plurality of pixel units. Each pixel unit includes a thin film transistor (TFT) and a liquid crystal capacitor.
When a gate on voltage is applied to a gate line, a corresponding TFT connected to the gate line is turned on, whereby a data voltage provided by a corresponding data line connected to the TFT is applied to the liquid crystal capacitor. At the same time, a common voltage is applied to the liquid crystal capacitor. When a gate off voltage is applied to the TFT via the gate line, the TFT is turned off, and a voltage difference between the data voltage and the common voltage is held by the liquid crystal capacitor. The voltage difference between the data voltage and the common voltage generates an electric field, driving liquid crystal variation. A resulting transmittance of light through the display panel provides display capability.
However, when the gate off voltage is applied to the TFT via the gate line, due to a parasitic capacitance formed between a gate electrode and a source electrode of the TFT, the TFT cannot be turned off completely, and a drain current is generated between the source electrode and a drain electrode of the TFT. Accordingly, voltage difference across the liquid crystal capacitor decreases. When the data voltage is applied with opposite polarities, a decreasing variation of the voltage difference due to the drain current being driven under a positive polarity is different from that under a negative polarity. Thereby flicker is generated, compromising quality of the display of the LCD device.
What are needed, therefore, are an LCD device and a driving method thereof which can overcome the described limitations.